chapman



\ f 1,640,437 Aug. 30,1927. v. J. CHAPMAN ELECTRIC WELDING Filed Feb. 16, 1925 2 Sheets-Sheet 1 Inventor: VernL J. Chapman.

Aug. 30,1927- v.J;cHAPMAN ELECTRIC WELDING Filed Feb. 16, 1925 2 Sheets-Sheet 2 PLS. 4.

)lbf f W.,

H'LS Attorney Patinted Aug. 30, 1927.

I UNITED STATES? 7 m40-,437 l, PATENT oFFicE.

VERNI J. CHAPMAN, OF SCHENECTADY, NEW YORK, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF N EWy YORK. y

ELECTRIC ,WELDITQ Application filed February chines wherein a backing member is 4arranged to be maintained in contact with the metal ofthe Weld during the welding operation, and has for its principal object the provision of an improved backing member which may be readily forced into the irrcgularitiesof the work in a manner to prevent burning of the parts to be welded. A

further object is the provision of an improved arrangement for stabilizing the welding arc. In the electric welding of metal parts, the edges to be united are commonly placed in juxtaposition upon a backing `member which may serve to support the workf With this arrangement, difliculty is frequently encountered due to the fact that the edges do not lie smoothly upon the backing member 2o and tlie metal is burned or an unevenness in the thickness of the Weld isproduced at v points where it is out of contact with the backing member. countered in electric are welding is unstableness of the welding arc. -In accordance with my invention, burning of the metal is *prevented by the provision of a flexible backing member adapted to be forced into the irregularities of the work, and the dili- :so culty of stabilizing the arc is largely avoided by the production of a magnetic field which is utilized to prevent bowing or lateral displacement of the arc. l My invention will be better understood :i5 from the following description when considered in connection with the accompany ing drawings and its scope will be pointed out in the appended claims.

Referring to the drawings, Figs. 1 and 2 are different views of an are welding machine in which my inventi. nhas been emfi" bodied; Fig. 3 is a sectional view of cer- 1"""1tain parts of the machine shown by Figs. and 2; Fig; 3a shows a modification of the parts shown byFig. 3; Fig. 4 shows amachine which differs in certain details from that illustrated by the preceding gures; in Fig. 5 is a viewl taken on section 5-5 of Fig. 4.

Figs. 1,2 and 3 show an are welding machine comprising pillars 1 and 2 mounted on a base'3 and arranged to support members 4 and 5 which form a trackway for the' welding head carriage 6. The carriage 6 is arranged to be driven along the trackway varound the nozzle through which the weld- A further difficulty en- Y v16, 1925. Serial No. 9,403.

in one ldirection by means of a. belt or sprocket chain 7, idle pulley 8, and a pulley 9 geared to the motor 10 in any suitable manner and to be driven vin the opposite direction by means of a` belt'or sprocket chain 11, idle pulleyy 12 and a pulley 13 which is likewisegeared to the' motor 10. An operating lever 14 mounted on the shaft 15 is provided for connectin the carriage 6 either to the chain 7 or to the chain 11 by means of a lu 17 or a lug 18 respectively,- aiid is adapte to be moved into its reverse or neutral position by means of adjustable stops '19 and 20 fwhen the weldindhead 21 has reached the limits of its trave A pipe 22 supported by the welding head 21 and provided with a nozzle -23 is arranged to create a current of air for dissipating the vapors tending to form a -deposit, of oxide ing electrode 21 is fed from a reel shown asv supported above the pillar 2.

It will be observed that the lower part of -the pillar 2 is surrounded by a rotatable cylindrical member 24 to which a fabricated 80 work support 25 is attached by means shown as members 26 and 27, pins 28 and brace 29. Catches 30 (shown more clearly in Fig. 5) are provided for locking the work support member in a position to permit welding of the work. The work support member may be of any suitable form. As shown in Fig. 3, it comprises a beam 31, a channel mem-- ber 32, plate members 33, 34 and 35 and a channel member 36, the plate members 33 and 34 bein welded to the channel member 32 and the c annel member 36 being welded to the plate 35.

A backing member shown as comprising flexible plates-37, which may be made of copper, steel or other suitable material, is supported upon the upper ends of a series of movable, hollow, cylindrical members 38 which are arranged to extend through the plate 35 and channeli36 and are provided` 100 at their lower ends with shoulders 39 adapt- 4ed to rest upon vfluid pressure responsive means shown' asv a flexible hose 40. Fluid for distending the hose 40 to bring the backing member 37 into contact with the work 105V 41 may be admitted through the pipe 42. It will be observed that the cylindrical mem'- bers 38 may be moved independently of one another to force the plates 37 into. the irregularities of the work in a manner to prevent burningl of the metal. Projections 38 may he provided on the cylindrical members 38 for supportingv the cylinders and work when the hose 40 is not disteiiiled und U- shaped members 37 may be provided to prevent working of thebacking member 37.

In tlie case of heavy work, the weight of the work 1may be utilized to maintain the seam in contact with the backing,r plate; but when lightfworlr is to be welded, it is de sirable thaty means be provided for holdingP t-he work against the pressure yexerted through the backing'- plat-e. Holding members, s hownf in Figs. 1, 2 and 3 as fabricated cantilever beams 43 and 44 and in Fig. 3" as rectangular beams 43 and 44', are provided for thls purpose. These beams, shown as supported by a pin 45 mounted between the members f 46 and 47, are arranged to be held in place by a yoke 48 pivoted to the channel member 32 at 49, and may be of any convenient form having suicient strength and L'allowing proper disposition of the heat produced by the welding operation. Plate members 46 and 47 are attached to the pillar 2.

In the operation of automatic arc Welding machines, it has been found that the arc tends to bow and wander about some- `what at different points along the seam. This unsteadiness or unstability of the arc seems to he the result of variations in the magnetic vfield surrounding the arc at different points along the seam. When operatina' machines of the type illustrated, thisl difficulty has been obviated to a large exl tent by the provision of coils 50 and 51 which are wound around beams 43 and 44, so that these beams form. the opposite poles 'of a magnet. y

In order to facilitate assembly of the work in the machine, an additional work support member 52 similar to the member 25 and angularly displaced therefrom may be mounted on the member 24, thus permittingr the work to be placed upon its support while thev machine is operating and to be immediately moved into alinement with the beams 43 and 44 upon the completion of a preceding welding operation.

The operation of the machine illustrated by Figs. 1, 2 and 3`will be readily understood without-detailed explanation. Assuming the work support member 25 to be disengaged from and swung out of alinement with the beams 43 and 44, the work may be assembled for welding by placing it on the backing member 37, swinging the member 25 around into alinement with the beams 43 and 44, rotating the yoke 48 Ainto engagement with the ends of the beams 43 and 44 and forcing; the backing plate 37 into contact with the work by means of air admitted to the hose 40 through the pipe 42, thus clamping the work between the' backing plate and beams in a manner to facilitate welding.

It will be readily understood that the work holder described herein may be inoditied in forni to adapt it to work of dill'erent shapes and that it has utility when utilized in connection with either manual or automatic weldingr operations.

Fig. 4 is a4r fragmentary view of a welding machine wherein the cantilever beams 43 and 44 of the machine illustrated by the 'preceding figures are replaced by beams 43 and 44 supported at opposite ends by the pillars 1 and 2 and wherein additional coils 51 are provided for stabilizing the are. ,The construction of the machine is otherwisel substantially the same as that ol' the machine previously deseribed and its operation will be readily understood without detailed explanation. As indicated by Fig. 5, the catches 30 are pivoted to a member 54 mounted on the pillar 1.

The embodiments of the invention illustrated and described herein have been sei lected for the purpose of clearly settingY forth the principles involved. It will be apparent, however, that the invention is susceptible of being modified in many ways ,to meet the different conditions encountered yin its use and I therefore aim to cover by the appended claims 4all modifications within the true spirit and scope of my invention.

What I claim as new and desire to secure. by Letters Patent of the United States, is,-

1. An electric are welding machine coin- ;-prising a backing member adapted to contact with the metal of the Weld, and a. backng member support including a plurality of parts arranged to be moved independently of one another for forcing said backing memiiber into the irregularities of the parts to be fywelded. l 2. A .welding apparatus comprising a ,backing member adapted to contact with the metal of the Weld, and a flexible hacking member support for forcing said backing;y member into the irregularities of the parts to be welded whereby burning of said parts isprevented.

3. A. welding;r apparatus comprising a hackng'member adapted to contact with the metal of the weld. a backing member. support including! a plurality of parts arranged to be moved independently of one another for forcing said backing member into the irregularities of the parts to be welded, and f fluid pressure means for controlling the movement of said parts.

4. An electric welding machine.compris ing a holding member, a flexible backing member adaptedto contact with the parts to be welded, and means arranged to be operated by uid pressure for forcing said parts into contact with .said holding member and for forcing said backing member into the irregularities of said parts.

5. An arc Welding apparatus comprising magnetizable holding membersv extending along the line of the seam tobe welded, and means for magnetizing said holdin members to produce a ma etic field irected across and extending a ong the line of the Weld. t

6. An electric arc welding machine comprising magnetizable holding members ex'- tendin along the line of the seam to be 'Welde means adapted to clamp the Work against said holding members, and means for magnetizing said holding members to produce a magnetic field directed across and eitending along thev 'line/ of the Weld.

- 7. An"e1ectric arc Welding machine comprising holding members extendin along the line of the seam to be Welded, a acking member adapted tocontact with the parts to be Welded, and means arranged to be` operated by duid pressure for forcin said backingmember into contact With sai parts to clamp 4said parts to said holding members.

8. jAn electric welding apparatus comprising a'lexible backing member adapted to contact with the parts to be4 Welded, and means comprising a distensible hose extend-Y ing along the line of the weld for forcing said backing member against said parts.

9. A Welding apparatus comprising a ilex ble backing member adapted to contact with the parts to be Welded, a series of` independently `movable supports for said backing member', and Huid pressure-responsive means for moving said supports to force said backing member into the irregularities of said parts.

InA witness whereof, Ilhave hereunto set my hand this 14th day of February, 1925. A VERNI J. CHAPMAN. 

